Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and...
-
Upload
curtis-collins -
Category
Documents
-
view
223 -
download
0
Transcript of Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and...
![Page 1: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/1.jpg)
Atmospheric Corrosion Testing
Comparison of Electrodeposited Hard Chrome
to HVOF WC/17Co and Tribaloy 400
Three-Year Atmospheric Exposure
Exposures Conducted at
Naval Research Laboratory
Marine Corrosion Test Facility, Key West, FL
Report Prepared by Paul Natishan and Bruce Sartwell
Naval Research Laboratory
![Page 2: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/2.jpg)
Atmospheric Corrosion Testing
Substrate Materials: 4340 steel and 7075-T73 aluminum alloy
Substrate Preparation: For EHC, grit blast with 180-220 grit Al2O3
For HVOF, grit blast with 54 grit Al2O3
Coating Deposition:EHC deposited at NADEP Jacksonville following MIL-STD-1501; on 7075
alloy, 0.0015-inch-thick sulfamate Ni deposited prior to Cr
WC/17Co deposited at NADEP Jacksonville using hybrid Diamondjet gun, hydrogen fuel, Diamalloy 2005 powder
Tribaloy 400 deposited at Southwest Aeroservice using Jet Kote II, hydrogen fuel, Stellite T-400 powder
Coating thicknesses of 0.004 inches
Tested as-deposited (no grinding)
Epoxy masking used on non-coated surfaces
![Page 3: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/3.jpg)
HVOF and Hard Chrome Coatings on 4340 SteelAtmospheric Exposure For 3 Years
Before Cleaning
![Page 4: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/4.jpg)
HVOF and Hard Chrome Coatings on 4340 SteelAtmospheric Exposure For 3 Years
After Cleaning
![Page 5: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/5.jpg)
HVOF and Hard Chrome Coatings on 4340 SteelAtmospheric Exposure For 3 Years
Before Cleaning
![Page 6: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/6.jpg)
HVOF and Hard Chrome Coatings on 4340 SteelAtmospheric Exposure For 3 Years
After Cleaning
![Page 7: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/7.jpg)
PROTECTION RATINGS FOR 4 MIL COATINGS OVER 4340 STEEL (PLATES)
0 2 4 6 8 10 12
WC/Co *
Triballoy 400 **
Hard Chrome, with nickelsublayer
Protection Ratings (10 = Best)
Edge
Face
** "T-400" (Stellite): 60% Co, 28% Mo, 9% Cr, 3% Si* Diamalloy 2005 (Sulzer-Metco): 83%WC, 17% Co
![Page 8: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/8.jpg)
HVOF and Hard Chrome on 7075 AluminumAtmospheric Exposure for 3 Years
Before Cleaning
Pits
![Page 9: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/9.jpg)
HVOF and Hard Chrome on 7075 AluminumAtmospheric Exposure For 3 Years
After Cleaning
Pits
![Page 10: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/10.jpg)
HVOF and Hard Chrome on 7075 AluminumAtmospheric Exposure for 3 Years
Before Cleaning
Pits
![Page 11: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/11.jpg)
HVOF and Hard Chrome on 7075 AluminumAtmospheric Exposure For 3 Years
After Cleaning
Pits
![Page 12: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/12.jpg)
HVOF and Hard Chrome on 7075 AluminumAtmospheric Exposure For 3 Years
After Cleaning
Pits
![Page 13: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/13.jpg)
PROTECTION RATINGS FOR 4 MIL COATINGS OVER 7075 ALUMINUM (PLATES)
0 2 4 6 8 10 12
WC/Co *
WC/Co *
Triballoy 400 **
Hard Chrome, with nickelsublayer
Protection Ratings (10 = Best)
Edge
Face
** "T-400" (Stellite): 60% Co, 28% Mo, 9% Cr, 3% Si* Diamalloy 2005 (Sulzer-Metco): 83%WC, 17% Co
(edges epoxy-masked)
![Page 14: Atmospheric Corrosion Testing Comparison of Electrodeposited Hard Chrome to HVOF WC/17Co and Tribaloy 400 Three-Year Atmospheric Exposure Exposures Conducted.](https://reader035.fdocuments.us/reader035/viewer/2022062320/56649d045503460f949d75a5/html5/thumbnails/14.jpg)
Summary
1. On 4340 steel, the HVOF WC/Co coating outperformed the EHC and HVOF T-400 coatings.
2. On 7075 aluminum, in general the EHC coating performed best.
3. On 7075 aluminum, two samples of a smaller dimension (3 x 4 inches) had protection ratings that were better than the EHC coatings on the 4 x 6 inch samples.
4. Some general corrosion of the WC/Co coatings was observed.